Device for stopping back flashings of the flames in pipings for feeding gases or gas mixtures



Feb. 5, 1929. 1,701,276

C. SCHRAUB DEVICE FOR STOPPING BACK FLASHINGS OF THE FLAMES IN PIPINGSFOR FEEDING GASES OR'GAS MIXTURES Filed Dec. 27, 1927 III - l N\/ENTEIR: I M 3W ,A'ITE] NEJ.

CHRISTEE SCHBAUB, 0F MAINZ, GERMANY.

DEVICE FOR STOPPING BACK PATENT OFFICE.

FLASHINGS OF THE FLAMES IN PIPINGS FOR FEEDING GASES 0R GAS MIXTURES.

Application filed December 27, 1927, Serial No. 242,928, and in GermanyDecember 29, 1926.

and pipings against the danger of fire and explosion.

The known devices arranged hitherto for thispi'irpose in pipes or tubesfor feeding gases or gas mixtures comprise an intermediate piece inwhich either a non-return valve with a safety valve, or a cooling bodywithout a safety valve is arranged, or else protecting nets are providedin the pipings. In case of back flashing of the flame the knownnon-return valves involve the danger of through-firing either becausethe inertia of a non-return valve is greater than the rate of i nitionof the exploding gases, or because tfie fresh gases ignite by directcontact with the still burning return gases on re-opening of thenon-return valve. This danger of through-firing is not even removed, ifa non-return valve, loaded with a heavy spring, is provided which opensonly during the suction stroke of the internal combustionengine and bywhich a permanent smaller weight of charge and therefore a decrease ofuseful work is obtained only. This latter drawback in a more or lessdegree have also all known non-return valves, because their guidesrestrict the normal cross section of the pipe. In the known coolingbodies and also in the known protecting nets the heated explosiongaseshave, in case of back flashing of the flame, no other opportunity ofexpansion and must pass through the protecting device. Cooling bodiesand protecting nets have always a limited heat capacity only. Therefore,as a result of constant back flashings of flames which in connectionwith internal combustion engines are produced by many disturbances, forinstance improper composition of the gas mixture, fracture of thesuction valves during run a. s. 0., the danger exists, that the coolingbodies or protected nets are super-' heated and the explosion extendsfurther.

According to the present invention the known parts are combined in a newand advantageous manner and known parts are arrange and formed in a newand advantageous manner. So, for instance, protecting nets are providedin a new manner at the joints of the intermediate piece fitted withsafety valves, which nets prevent the contact of the igniting flame withthe fresh gases in "known catch cup and simultaneously in a case of backflashing of flame. Further the guide of the non-return valve is arrangedin a new manner in the intermediate piece of great cross section and thespring of this valve is in a new manner so arranged and tensioned thatit just su ports the weight of said valve; moreover 518 position of thevalve disc may, with regard to the valve seat, be adjusted in a newmanner by means of a threaded nipple without aflecting the tension ofthe spring. The valve disc itself is formed in a new manner completelyas a cup. By the Whole new arrangement is obtained, that no flowresistance during ordinary use occurs, while on 'back flashing of theflame the latter acts upon the cup of the non-return valve and safelycloses thevalve. The non-return valve is furthermore by means of itsspindle connected to the well new manner bodily combined in the interiorof the intermediate piece in such manner that back flashing of the flameis in the safest manner taken up by the catch cup and the non-returnvalve is closed instantaneously. The known cooling bodies are in a newmanner arranged in an intermediate piece provided with safety valves. Asa result of this arrangement the overpressure prevailing in the pipingon back flashing of the flame may be discharged through the safetyValves. Moreover the known cooling body is combined with the non-returnvalve in a new manner and the arrangement is such, that on back flashingof the flame the non-return valve can only come into contactwith thecooled back flashing gases. At the same time the known cooling body isformed in a new manner as guide for the non-return valve. Furthermorethe known cooling body and the non-return valve with front, the catchcup, however behind the 100 cooling body. In this arrangement the backflashing flames not only directly impinge upon the catch cup and causeinstantaneous closing of the non-return valve, but the latter remainsalso constantly in cool gases. 105

All combinations are "connected in a new manner to a device countin theback flashings of the flames, where y the opening movements of one ofthe safety valves are transferred to an indicating device arranged 11petrol. "This mixture of heavy petrol and air tends very much tocondense in the sucti on pipes.

To prevent such condensations the devices described above for stoppingthe back flashing of the flames may be provided with a jacket forsupplying said devices with a heating medium. To obtain a more intensiveand a more perfect heating suitable members of the construction (forinstance the arm-cross and the absorption bodies) are used for thispurpose and accordingly made hollow. Of course, special perforations ofthe casing could also be provided. The heating is effected in'knownmanner by the cooling water of the motor or by the exhaust gases. Thismethod of heating is preferably used, if the motor operates with heavyoils having a higher boiling point. A distance thermometer is employedfor controlling the most favorable heat condition of the fuel used. Forregulating the heat supply a throttle valve is arranged in the pipingsof the heat carrier. The heating of the device may also be obtained in aknown manner by electricity and this directly by surrounding the casingof the device with a heating element. This manner of heating may,however, also be effected indirectly by electrically heating a heatcarrier which in turn effects the heat exchange. The heating byelectricity also allows regulating of the heating conditions in widelimits.

In the accompanying drawing one mode of construction of. the deviceaccording to the invention is shown by way of example. Fig. 1 is' a'longitudinal section on line II of Fig. 2 and Fig. 2 is a plan View ofthe new device.

As shown in Fig. 1, the known intermediate piece a is, by means of thejoints 7) and 0, connected to the piping supplying the gases or gasmixture in such a manner, that the gases normally flow in the directionfrom 0' to Z). The known protecting nets 61 ,15 are arranged in the newmanner in the joints of the intermediate piece. In this piece a arearranged the known safety valves a 72 at the openings of whichprotecting nets are provided. A known arm cross arranged in a new manneris the great cross section of the intermediate piece, or alternately aknown cooling body e, constructed, however, in a new manner, serves as abearing for the parts i, g, h, 7c, in of the non-return valve. The valvehead i is in a new manner formed as a perfect cup and connected by meansof its spindle g in a new manner to the known catch cup it. valve head2' andthe catch cup h are in the interior of the intermediate piecebodily and advantageously so combined, that back flashings of the flamesdirectly act upon the catch cup. The spring is which, in case a catchcup is not used, bears against a washer fixed to the spindle, is juststrong enough, to carry the weight of the'movable parts a", g, it Bymeans of telescoping sleeves the spring is is protected against theaction of the hot back flashing gases. Without afiecting the tension ofthe spring, the position of height of the valve head i with regard tothevalve seat may be adjusted by means of the threaded nipple m. The.

cooling body 6, known per se in different constructions, may also, butin a new manner, be arranged alone in the intermediate piece a providedwith safety valves n if, so that the overpressure produced by backflashings of the flames may be discharged at once through the safetyvalves. In all combinations one of the safety valves, for instance thevalve n is connected by means of a Bowden wire to an indicating device,shown diagrammatically in Fig. 1. This indicating device substantiallyconsists of a The I counting work 1, driven by the shaft 2 upon which isfixed the ratchet wheel The pawl 4 is pivotally mounted upon the pin 5and is pressed by a spring 6 under light pressure against the ratchetwheel 3. The pawl 7 is pivoted upon the pin 5 and is also pressedagainst the ratchet wheel 3 by a spring 6?. The pawl 7 may be moved in astraight line and by-this movement the wheel 3 is turned. The Bowdenwire 0 transfers the movement of one of the safety valves upon that partof the pawl 7 which may be shifted in a straight line and which isalways returned by the spring 8.

The operation of the different combinations will be explained by thefollowing description The unobstructed flow of the ga'ses or gas mixtureis favored by the convex faces of the cups h and i directed towards thedirection of flow as well as by. the arm cross, or in place of this bythe cooling body e having a correspondingl free area of passage whichcross or w lich cooling body e being arranged in the great cross sectionof the intermediate piece a. I

contact of the igniting flames with the fresh gases is prevented bythe'protecting nets d d The back flashing of the flames acts upon theconcave surface of the valve head i or the catch cup h which is forcedbackward, causing an instantaneous closure of the valve. The burningback flashing gases are by passing through the cooler e cooled'to aharmless temperature. 7 tions the overpressure produced on backflashings of the flames escapes through the safety valves n n while atthe same time one of them, for instance the valve n transfers itsmovements by means of the Bowden wire 0 upon the indicating device.

In any of the constructions described above a casing or jacket 1) maysurround the intermediate piece a. This jacket 0 is provided with joints9 and 1' for connection to a circulating system of a heating medium.

.The heating medium may flow through the space formed between the casinga and the jacket 39 only, or, if desired, parts arranged inside thepiece a may be madehollow and be connected to the said space, so thatthe heating medium also flows through v these parts.

,A heat carrier, cooling water which has been heated by use, or exhaustgases, or an electrically heated carrier is introduced by the joint 9circulates in the space between the piece a and the jacket 17 and leavesthe device by way of the joint 1'. The intermediate piece a is thereforeconstantly heated, so that condensing of parts of the mixture at theinner surfaces of the piece a is absolutely prevented. Moreover by acorresponding regulation of the circulating amount of the heat carrierthe gas mixture normally passing through the piece a is subjected to anadditional heating, so that even in a severe winter the new device maybe used not only without any draw-backs, but moreover the advantage ofheating the gas mixture is obtained together with the protection againstback flashings. This means increased utilization of the fuel that isalso increased economy in operation.

Of course, many modifications may be made in the construction andarrangement of the parts of the device without departing from the spiritof the invention.

What I claim is:

1. In a device for stopping back flashings of the flames in pipings forfeeding gases or gas mixtures in combination, an intermediate piecehaving a greater cross section than the piping arranged in said piping,protecting nets at the joints of said piece, safety valves carried bysaid intermediate piece, a device operatively connected to one of saidsafety valves for counting and 'indicating the back flashings of theflame, a member surrounding the casing of said intermediate piece andmeans for supplying heat to said member for the purpose of heating thewhole apparatus. 2. In a. device for stopping back flash- With allcombina-' .ings of the flames in plpin ings of the flames in piping. forfeeding gases or gas mixtures in combination, an intermediate piecehaving a greater cross section than the piping arranged in said piping,a cup-shaped non-return valve in said piece, balanced in its weight by aspring and guided by its spindle passing-through an arm cross nets atthe joints of said piece, safety valves carried by said piece, a deviceoperatively connected to one of said safety valves for counting andindicating the back flashings of the flame, amember surrounding. theeasing of said intermediate piece and means for supplying heat to saidmember for the purpose of heating the whole apparatus.

3. In a device for stopping gases or gas mixtures in com ination an1ntermediate piece having a greater cross sectlon than-the pipingarranged in said p1p- 4. In a device for stopping back flashings of theflames in piplngs for feeding gases or gas mixtures in combination, anintermediate piece of greater cross section than the said pi ingarranged in said piping, a cooling b0 y carried inside said piece, asliding cup shaped non-return valve balanced in its weight and arrangedin the direction of flow of the gas mixture in front of the said coolingbody, protecting nets provided at the joints of the said piece, safetyvalvesfcarried by said piece, a device operatively connected to one ofsaid safety valves for counting and indicating the back flashings of theflame, a member surrounding the casing of said intermediate piece andmeans for supplying heat to .said member for the purpose of heating thewhole apparatus.

5. In a device for stopping back flashings of the flames in. pipings forfeeding,

back flashs for feeding v a cup shaped fixed in said .piece, protectinga cup shapednon-returnvalve balanced in its weight and guided in saidpiece, a

the back flashings of the flame, a member surrounding the casing of saidintermediate piece and means for supplying heat to said member for thepurpose of heating the whole apparatus,

6..In adevice for stopping back flashings of the flames in pipings forfeeding gases or gas mixtures in combination, an in termediate piecehaving a greater cross section than the piping arranged in said piping,safety valves carried by said piece, a

cooling body, a device operatively connected to one of said safetyvalves for countin and indicating the back fiashings of the ame, amembersurrounding the casing of said intermediate piece and means forsupplying heat to said member for the purpose of heating the wholeapparatus.

In testimony whereof I have afiixedmy signature.

'CHRISTEL SGHRAUB.

